A Microsoft 365 outage continued into November 13, disrupting Exchange Online email and features across the company’s business services. Microsoft’s incident notice, reproduced from its administrative console by the University of Pennsylvania, still listed service degradation.
Users could face inaccessible Outlook mailboxes and delayed delivery. The impact also reached Copilot, Defender and Purview features. Microsoft said most core Teams functions, including calls and meetings, remained available, while Exchange-dependent features such as calendars could fail. Access to files stored directly in SharePoint remained functional.
In its November 13 update at 06:54 UTC, Microsoft reported limited progress restoring capacity and said it was adding virtual machines while checking server performance and deployed fixes. That update did not establish a final root cause or announce full recovery.
Microsoft said it was unaware of malicious activity causing the incident. Administrators should track MO1550821 and EX1550543 through the service-health dashboard and assess which workflows depend on the affected services.
